Scientists using observations made on a very large telescope, found that 10 billion years ago, that is, in the era of the formation of most galaxies, in massive galaxies with active star formation, the "ordinary" baryonic substance predominated. Now the influence of mysterious dark matter on galaxies is much greater, according to the website of the European Southern Observatory.

The researchers measured the rotation of six massive galaxies with active star formation in the far universe, at the time when most galaxies were formed, that is, 10 billion years ago. The result of their measurements was unexpected: unlike spiral galaxies in the modern universe, the outer regions of these distant galaxies rotate more slowly than internal galaxies, which means that there is less dark matter than expected.

It turned out that three or four billion years after the Big Bang gas in the galaxies had managed to concentrate in the flat rotating discs, and the dark matter formed around them a spherical halo, much longer than the halo around the current galaxies. And presumably, billions of years passed before dark matter condensed to such an extent that its influence began to affect the rates of rotation of the outer regions of modern galactic discs.

This explanation is consistent with the fact that, as observations show, the early galaxies are much richer in gas and much more compact than modern.

Dark matter is a mysterious substance, which accounts for about 75% of the mass of matter in the universe. According to researchers, in each galaxy it is 8-10 times more than the visible. This substance makes the stars stay in place, and the dark energy causes the universe to expand with acceleration.

Earlier it was reported that scientists have developed a "escape plan" of information from a black hole that would not violate all the laws of classical and quantum physics, and talked about how such an experiment could be carried out in practice. It will require an astronaut who will be at the "event horizon", an electron that he will hold in his hands, and information about the direction of movement (back) of the black hole. Measuring the spin of a black hole and the properties of the particles of light generated by Hawking radiation, the astronaut "releases" the electron beyond the event horizon.